Automatic controlled electric time switch



Aug. 28, 1934. R-THAYER 1,971,799

AUTOMATIC CONTROLLED ELECTRIC TIME SWITCH Filed June 15, 1930 Patented Au 28, 1934 UNITED STATES PATENT tics AUTOMATIC CONTROLLED ELECTRIC TIME SWITCH 4 Claims.

My invention relates to improvements in mechanically controlled, automatic switches for operating an electric circuit at predetermined and variable time periods and may be used on any electric circuit requiring tirne-measurement.

This invention consists of indicating dials divided to show time intervals, mounted on a clock, with movable indicators which rotate counter clock-wise, and shows the exact position of the key to the switch operation and shows also the diminishing time interval, marking the time which must elapse prior to the instance of operation.

This invention is attachable to an ordinary spring driven clock, or an electric clock operated by current pulsations, the principle of operation being by gears rigidly attached to shafts which carry the indicators and keys, the proper ratio being maintained between the drive gear or power gear of the clock and the dial gears so that the indicators pass over the proper number of divisions on the dials for a given time. The shafts rotate and slide, and when the keys are in alignment with a fixed key-way, a coil spring in constant pressure against the meshing of the gears,

forces the dial gears out of mesh with the drive gear. When the shafts slide they operate a ribbon spring switch which is under lighter tension than the coil springs on the shafts and opposed to them, thereby moving the switch into, or outof, contact with current contact points.

I attain this object by the mechanism illustrated in the accompanying drawing, in which- Figure 1 is a vertical front view of the device attached to a clock and shows the dials and gear arrangement; Figure 2 is a vertical back view of the device showing the rigid manner of attachment to the clock, the gear arrangement and the locations of the spring switch with wire connections; Figure 3 is a perspective drawing showing the device with the drive wheel of the clock, with the gears out of mesh, the dials, and indicators and keys in position as they would be with circuit disconnected and the coil springs expanded and in position on the shaft pushing the gears out of mesh; Figure 4 is a vertical side view of the device showing gears out of mesh, coil springs expanded, ribbon switch under tension and disconnected from contact which controls the shunting on the current, and shows the device in the condition when not set for operation; Figure 5 is a vertical side view as in Figure 4 but with these exceptions, the shafts are pulled back, 'gears in mesh, keys and key-ways out of alignment and the shafts turned with the indicators pointing to some other divisions on the dials other than zero or twelve, and shows the ribbon switch down on the contact operated by one gear and away from the contact operated by a second gear, and is in condition when set for a complete operation of a circuit for shunting on and oif at any set and predetermined interval. Figure 6 shows plate A which is of hard rubber, composition, fibre or other insulating material.

In my drawing similar letters refer to similar parts throughout the several views.

In Figure 3, R and 8 represent metal screws and are the places of attachment for any out or interrupted electric circuit which it is desired to control by time-measurement; for instance: cut any wire carrying an electric current, attach one end to'R and the other end to S, the current is therefore interrupted until certain functions have been performed in the device which will re-establish contact between ends of the cut wire, and this contact is controlled at two points, i. e. when the ribbon switch C touches plate B and when the shaft 0' touches the ribbon switch C. In order to have the current pass through the contact B-C, it is always necessary that contact O'C (between the shaft and the ribbon switch) be first established, as the point S is electrically connected with the shaft 0' which is an electrical conductor and is all metal, and is unlike shaft 0 which carries an insulating tip N which prevents passage of an electric current through shaft 0 to the ribbon switch C. It is stated here, that while the drawing shows a ribbon switch, under certain conditions requiring larger area than permit ed by a thin strip of spring metal, metal levers may be used operated by coil springs, to control high voltage as in street lighting systems or signals.

Plate A is the frame or base upon which the device is biult. It has two shaft bearings which may be babbitted, and key-ways L and L. Plate A is attached to the clock worss M as shown in Figure 2 by an arm and screr. bolts, and is shown in all figures.

Metal strip B, curved to form, is attached to plate A by screw bolt R which is a point of attachment for a lead wire of the electric circuit to be intercepted, and is shown in Figures 23 4-5 Spring metal ribbon switch 0, shown in Figures 2-3-45, curved to form, is attached to plate A by a machine screw with head countersunk in plate A to prevent possible electrical connection with gears J and J when they are close toplate A as shown in Figure 4. The ribbon switch C has a tendency to press against plate B at one end and against plate A over the shaft bearing L. Separator D, of fibre or insulation, is bored for screw bolt S, is cylindrical and truly formed with parallel ends to hold plates A and E apart in parallel planes and the plates A and E rigidly in place when screw bolt S is tightened, as in Figures 3l and 5.

The metal plate E, Figures 1-34 and 5, has dials F and F engraved, pressed or imprinted in the metal. Dials F and F, respectively,

carry twelve equal major divisions representing visions, governed by the diameter or scale uponwhich the device is made, to represent a group of minutes, single minutes or even seconds. The H major divisions are consecutively numbered,

counter clock-wise, and slots Q and Q, respectively, are cut through the dials F and F at zero or twelve, to allow for an indicator.

Metal shafts O and O are true and rotate, and slide in parallel through the fixed plates A and E. Shafts 0 and 0, respectively, have needle indicators P and P, keys I and 1, rubber, fibre or composition caps G and G and gears J and J. The gears J and J are pressed onto the shafts O and 0, respectively, at true right angles with the plane of the gears and the axis of the shafts at 90 degrees toeachother, and do not move on the shafts but are rigid with them. Shafts O and O are threaded at the indicator ends to receive the threaded caps G and G. Shaft O is threaded at the key end to receive a cap N of insulating material. Both shafts O and O are of equal length. 1

The gears J and J mesh with the barrel or drive gear K of the clock M. The number of teeth and diameter of the gears J and J is determined by the size of, and the number of teeth of, and the time necessary to make one revolution by, the drive gear K. It is the object to have gears J and J turn once around in twelve hours. The more teeth available in gears J and J the closer the indicators P and P may be set.

Coil springs H and H are sufficiently loose on the shafts O and 0, respectively, and press against plate E and the gears J and J tending to force plate and gears apart and thus, the gears J and J out of mesh with drive gear K.

To operate the device pull the shaft 0 back by means of the cap G, turning slightly to let the teeth of gear J pass through the teeth of gear K which is any driven gear of a clock movement and part of the clock; turn so the indicator P marks sometime ahead on the dial which has counter clock-wise marked divisions and which shows time measured by the dial divisions. The indicator is now set for a span of time to elapse before the current switch is to be turned on. Let cap G back freely, and the teeth of gear J will mesh with the teeth of gear K and key I which has been pulled out of the key-way L, 'will rest on and ride on the bushing or bearing in plate A and will keep the gears in mesh until the key is ment with key-way L when it will drop into the key-way because of the pressure of coil spring H; this allows the metal shaft 0 to come into contact with spring switch C and establishes an electrical connection; provided, the indicator P on shaft 0 has in a similar manner been set with shaft 0 pulled back allowing spring switch 0 to press against plate B makingelectrical contact which will be broken later when indicator P, which has been set on dial F for a longer interval of time than indicator P was set for on dial F. 'When indicator P gets back or is turned back to zero on the dial by the clock mechanism then key 'I will fall into key-way L and the spring switch C N may be omitted if shaft 0 is shortened to leave space between 0 and 0 when B-C are in contact.

Figure 5 shows both shafts O and O pulled back and indicators set; at a predetermined time shaft 0 can be setto slide and make electrical contact with switch C to turn ,on the current, later shaft 0 having been set to break contact at BC will turn off the current, leaving the condition as shown in Figure 4.

I claim:

1. In a time switch consisting of a device for closing and opening an electric circuit, a rotating shaft carrying a gear fixed thereto movable into and out of mesh with a drive gear of a clock, akey-way, a key and indicator in alignment on said shaft, a spring which forces the movable gear out-of mesh, releasing the shaft from rotation when the key or indicator is turned into exact alignment with said key-way therebyv allowing the shaft to slide forcibly against a contact spring switch of lighter tension for the closing or opening of an electric circuit.

g 2. In a time switch, in combination, a clock driven gear, a rotating and sliding shaft with a gear fixed to the shaft and held inplace for meshing with the clockgear by a plate or bearing block, a dial plate with a dial marking time divisions, a key-way in the bearing block, a key and an indicator mounted on the shaft which is turned by meansof the clock gear with the indicator moving'across the divisions on the dial, a

spring which forces the slidable shaft against a contact switch when the key on the shaft is turned into'alignment with key-way in the bearingblock, a switch that is closed or opened by means of the sliding shaft.

3. In a time switch consisting of a device for closing and opening an electric circuit, two slid- *1 ing and rotating shafts, gears attached to each shaft moved by springs under compression out-of mesh with a motor driven gear of a clock, a bearing plate with key-ways for mounting the shafts, a key on each shaft which holds the gears in mesh, a contact switch against which the ends of the rotating and sliding shafts press when the shafts are turned and the keys drop into the key-ways.

4. In a time switch, in combination, a rotating and sliding. shaft with an insulated tip, an attached gear which meshes with a gear of the clock, a key on the shaft, a key-way in a plate or bearing block attached to the clock, a spring which pushes the shaft gear out-of mesh when the key on the shaft is in alignment with the keyway, a switch with connecting terminals contacted by means of the rotating and sliding parts.

ALBERT ROWLAND THAYER.

its 

